1. Field of the Invention
Aspects of the present invention relate to a system and method of converting a red-green-blue (RGB) value to a red-green-blue-white (RGBW) value by using a white (W) value extraction, which is applicable to all display devices that can be expressed using sub-pixels (for example, a transmission display device such as a liquid crystal display (LCD) device and a plasma display panel (PDP) device, a transreflective-type display device such as an electronic paper, a self-light emitting system such as an organic light emitting diode (OLED), etc.).
2. Description of the Related Art
Conventionally, various types of schemes exist to extract a red-green-blue-white (RGBW) value from a red-green-blue (RGB) value. Generally, such conventional schemes to extract an RGBW value use a simple algorithm. For example, a W value may be conventionally computed by applying a Min( ) function to an RGB value. Similarly, an RGB value may be converted into a YUV value, and then again converting the YUV value into an RGBW value.
However, according to the conventional art, when using the Min( ) function, a minimum value of the RGB value is used. Therefore, the entire gamut boundary of a system may not be sufficiently used. Also, when performing a color space conversion using the YUV value, a relatively greater weight may be assigned to a Y signal. Therefore, the entire saturation may be deteriorated.
Accordingly, there is a need for a method of extracting a W value that can maximally use the gamut boundary of a color space, while appropriately reflecting a luminance value and a saturation value of the color space.